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<html>
  <head>
    <title>Regression test for CR573921</title>
    <style>
      @import url(a)
    </style>
    <script>
      function f() {
          window.parent.postMessage(1, '*');
          var t = document.documentElement.outerHTML;
          document.writeln(t);
      }
    </script>
    <style onload="f()"></style>
  </head>
  <body>
    <iframe></iframe>
  </body>
</html>
